Your correspondence

Set the record straight
My sympathies are with David Holden (“Smarting”, Letters, July 9), for I was caught on a motorway doing 46mph in a 40mph average-speed-check zone. During my subsequent Community Speedwatch course, we were told cameras supposedly record only those cars going over the 10% + 2mph limit. Little wonder motorists feel confused and penalised.David Smith, Sandhurst, Kent

Crossing the line
Is David Holden aware that 50mph + 10% + 2mph is 57mph? In any case, the formula is merely a guideline. One assumes his car was caught by an enforcement camera, which may well be set to commence recording at 10% + 2mph; unfortunately for him, cameras, unlike police officers, have no discretion. Penalty fines can commence at 1mph above the maximum permitted speed. There has to be a red line. Best to stick to the limit.Melvyn Bunting, Birstall, West Yorkshire

The talking cure
Autonomous vehicles are able automatically to keep within prevailing speed limits, so why is this same technology not being put into all new cars as standard? David Holden’s car could then talk to the “smart” highway and keep within the limit. Presumably the police would also be delighted.Donal Fellows, Midleton, Co Cork

Save us from eco-porridge
It sounds as if the Bugatti Chiron is undriveable in London (“I’ve done fast and silly fast, but this is flaming ridiculous”, July 9) and won’t tow a caravan. You can’t legally exceed 70mph in it, so what’s the point? The wonderful, pioneering, joyous engineering, that’s what, and VW is to be congratulated on its brave, imaginative, irreverent, hugely fun approach. Someone has to do it or we all sink into a dreary vat of politically correct eco-porridge.Peter Cartledge, Tetchill, Shropshire

Spare parted
Our used BMW did not come with a spare key. We were assured we would receive one, yet 18 months later we’re still waiting. Is it too much to expect a dealer to fulfil a promise?Emma Kirk, Cheam, Surrey

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